kowari: database for the storage, retrieval and analysis of RDF and OWL metadata; non-relational, written in Java.

ARC - RDF and SPARQL for PHP developers is a lightweight, SPARQL-enabled RDF system for mainstream Web projects. It is written in PHP and has been optimized for shared (or otherwise performance- or privilege-limited) Web environments.

3store - developed in the Intelligence, Agents and Multimedia research group at Southampton University, as part of the AKT Project.

Ruby On Rails and ActiveRDF - HCLSIG subgroup task - to produce a Ruby On Rails and Active RDF implementation of the BioDash eclipse (Java) based gui so that we can show that the functionality shown in BioDash can be implemented using web based technologies.

Ruby RDF was an experimental RDF system implemented in Ruby. It is no longer under active development.

Sparta is an Python API for RDF that is designed to help easily learn and navigate the Semantic Web programmatically. Unlike other RDF interfaces, which are generally triple-based, Sparta binds RDF nodes to Python objects and RDF arcs to attributes of those Python objects.

D2R Server - SPARQL endpoint for relational databases; combines the D2RQ API and Joseki SPARQL Server to map a database's contents into a virtual RDF graph that can be accessed over the SPARQL protocol. It is bundled with a Jetty webserver and aims at being easy to set up and use.

KAON Reverse is a prototype GUI for mapping relational databse content to ontologies.

RDFizers are tools that allow to transform existing data into an RDF representation.

BioDash is a Semantic Web prototype of a Drug Development Dashboard that associates disease, compounds, drug progression stages, molecular biology, and pathway knowledge for a team of users (built on Haystack)

RDF crawlers

RDF crawler - uses Jena RDF toolkit to spider the web gathering up semantic web data and to store it in any of Jena's backend stores

SweDE is built on the Eclipse IDE, includes an OWL editor with helpful features like syntax highlighting, autocompletion, and error-detection. It also currently integrates existing tools like the OWL Validator, Kazuki (OWL to Java code generator), and DumpOnt (Ontology Visualizer).

Ontology Managers

KAON is an open-source ontology management infrastructure targeted for business applications. It includes a comprehensive tool suite allowing easy ontology creation and management and provides a framework for building ontology-based applications. An important focus of KAON is scalable and efficient reasoning with ontologies.

Web Services

The Universal Information Service Browser (UISB) Project The aim of the UISB Project is to investigate and improve interaction with Information Services used in a range of distributed environments, in the first instance these will include Web Services, UDDI and the Jini Lookup Service.